Synthesis, spectroscopic, fluorescence properties and biological evaluation of novel Pd(II) and Cd(II) complexes of NOON tetradentate Schiff bases

The solid complexes of Pd(II) and Cd(II) with N,N/bis(salicylaldehyde)4,5-dimethyl-1,2-phenylenediamine (H2L1), and N,N/bis(salicylaldehyde)4,5-dichloro-1,2-phenylenediamine (H2L2) have been synthesized and characterized by several techniques using elemental analysis (CHN), FT-IR, H-1 NMR, UV-Vis spectra and thermal analysis. Elemental analysis data proved 1:1 stoichiometry for the reported complexes while spectroscopic data indicated square planar and octahedral geometries for Pd(II) and Cd(II) complexes, respectively. The prepared ligands, Pd(II) and Cd(II) complexes exhibited intraligand (pi-pi*) fluorescence and can potentially serve as photoactive materials. Thermal behavior of the complexes was studied and kinetic parameters were determined by Coats-Redfern method. Both the ligands and their complexes have been screened for antimicrobial activities. (C) 2013 Elsevier B.V. All rights reserved.